19.567 — Thesis Preparation Solution

It can be verified on the Internet that at least at some time Athena minicourses (usually seen without the hyphen) were taught in 3-343 at the hours indicated. It's likely that a course listing with a description of each course).

• This page gives a schedule of the courses for some year, matching the room and times, except that they are also taught on Fridays.
  
• This one gives descriptions of mostly the same courses. It's likely a page with descriptions like these may have been available in many Athena clusters, possibly with the schedule on the other side.
  
• This one says they were discontinued in 2004 (and points out that some of the subjects were no longer relevant by 2010 when the page was written).
• This one indicates that minicourses were being taught again in 2012.

However, none of this helps us find the descriptions of the courses taught in 1997-1998. They do not appear to have been in the course bulletin.

It's likely that this was some form of book code, perhaps indexing by course, line, and word (taking the first letter) or course, word, and letter. Note the repetition in the third triple of numbers in the first column and the last triple. The answer, known from the meta solution, is CRYPTOGRAPHY, consistent with reading the results down the columns so that the repeated triple represents Y.